Narrow veneer strips are typically used in the production of laminated veneer boards and beams, which are commercially available, for example, under the trade name PARALLAM.RTM.. Until now, the method for producing these veneer strips has been to peel relatively large diameter boles in veneer peeling machines and then to cut these peeled veneers, in so-called clippers, into strips of a length of approximately 80 cm. The strips have then been checked manually for flaws or attached pieces of branch. This production method is laborious and expensive.
To avoid this laborious and expensive production method, German Patent 195 04 030 C1 has proposed a process and an apparatus that make it possible to produce, in addition to the main product of a solid-wood beam, a secondary product of veneer strips from the edge regions of the bole. For this purpose, a severing tool, which may be designed as saws, is used to divide up the bole at intervals in its edge regions. These intervals correspond to the widths, transverse to the fiber direction of the bole, of the veneer strips to be produced. Thereafter, the bole prepared in this way is passed into the region of frustoconical cutter disks, which are constructed in the manner of the known profiling cutters. On these cutter disks, the cutters are offset helically with respect to one another, and the cutters, from the smallest cutting circle to the largest cutting circle, are set back with respect to the following (trailing) cutter by the thickness of one sliver, e.g., 1.5 mm.
Such cutter disks or profiling cutters have proven successful in the production of coarse chips, but are unsuitable for the production of narrow veneer strips of a length of 100 mm to 500 mm, because they do not have a wood-guiding surface. Without the wood-guiding surface it is not possible to make a severing cut for producing a uniform material thickness, especially at the high through-passage speeds of 50 m/min and above, as required in industry, without creating cracks in the direction in which the fibers run.
The process and apparatus explained in German Patent 195 04 030 C1 can only achieve reasonably uniform sliver thicknesses and crack-free veneer strips if the bole-advancement speed is reduced considerably. However, this reduced production time does not fulfill the requirements for cost-effective production.